Definition A.1 (Definition 16.5 in [1]}) 
A collection \(\triangle =\lbrace T_1,\ldots ,T_N\rbrace \)  of \(N\)  tetrahedra is called a tetrahedral partition of \(\Omega =\cup _{h=1}^N T_{h}\)  provided that any pair of tetrahedra in \(\triangle \)  intersect at most at a common vertex, along a common edge, or along a common triangular face.

